a team allowed to invite 15-20 is a good idea. maybe even push it to 30. it would be like the whole "hey can you get me on your roster"... i really like that idea. remember you don't even need a huge club to have an afterparty.
look at boston last few years ... they had their afterparty in the ballroom of the hotel with a couple of bars around the ballroom.
10 teams(20 people each (after adding people to roster)) = 200 people. 125 will go to the afterparty.
10 teams, each with an additional 20-25 spots for PARTY ROSTER. a possible 250 more people.
(at this point im thinking... i hope that my math is right

)
so we are looking at 375-400 people that's not too bad for a hotel ballroom. maybe have a few extra tickets that you have to by REALLY early.
i would put vick on my roster... but not sulmoney.